The new configuration is making its debut this week in Kenworth's booth (No. 12137) at the Great American Trucking Show in Dallas.

"By equipping a Kenworth T800 with dual LNG fuel tanks, operators now have the option of running the truck up to 700 miles on a single fueling," said Alan Fennimore, Kenworth's vocational marketing manager. "This option doubles the operating range of a typical LNG-powered Kenworth T800 equipped with a single LNG tank, making the truck a better choice for long haulers with slip-seat or drop-and-hook operations and for regional haulers whose drivers travel long distances, but still return home at the end of their shifts."

The Kenworth T800, when equipped with the Westport GX, can be ordered in a gross combination weight (GCW) of up to 80,000 lbs. for over-the-road operation, with additional ratings exceeding 100,000 lbs. available for certain applications. For the T800, the GX engine is available in power ratings from 400 to 475 hp and torque ratings from 1,450 to 1,750 lb-ft, giving it similar horsepower and torque ratings to its diesel engine counterparts. Since natural gas can be produced in North America, it helps reduce dependence on foreign oil sources.

For the dual LNG tank configuration, Kenworth uses a Dewar flask (or cryogenic tank) system that is like a large Thermos bottle inside a metal cylinder. Each LNG fuel tank, which is designed to keep the fuel in its liquid state at minus 260 degrees Fahrenheit, can hold up to 60 diesel gallon equivalents (DGE) of fuel. The dual LNG tank configuration is only available on the Kenworth T800, equipped with a day cab or the Kenworth Extended Day Cab.

"By providing a dual LNG tank configuration, Kenworth is helping truck operators take full advantage of plans by major fuel providers to install a larger network of natural gas fueling stations across the United States," Fennimore said.

Over the next two to three years, Chesapeake Energy plans to work with Clean Energy Fuels to install 150 LNG publicly accessible fueling stations for heavy duty trucks along major interstate highway corridors. Plus, engine manufacturer Westport Innovations of Vancouver, B.C., and Shell announced last year the launch of a co-marketing program in North America aimed at providing customers with a better economic case for adopting natural gas-powered vehicles by addressing fuel supply and customer support.

Already UPS operates a number of LNG-powered Kenworth trucks along the Salt Lake City to Las Vegas corridor and UPS along with CR England operates LNG-powered trucks from southern California to Las Vegas, Fennimore noted.

"With the addition of new fueling stations, more and more truck operators will be looking seriously at adding natural gas power as an alternative to diesel," he added.

Still, Fennimore cautions that a dual tank configuration is not for everyone.

"We suggest truck operators who are considering adopting natural gas take a closer look at their operations to determine if they truly need an additional tank," Fennimore said. "If they have enough deliveries or payloads in the additional 200 to 300 miles to justify the added cost, then they should have their LNG-powered trucks equipped with the additional fuel tank."

Since the dual tank configuration is only available with the Westport GX engine featuring Westport's high-pressure direct injection technology, the truck must also have the space below the cab for the emission controls system, which can take an additional 4 to 5 feet of frame rail space. That means the dual tank configuration must be installed on a Kenworth T800 with a minimum 220-inch wheelbase.